Comment 8 for bug 1811905

Reviewed: https://review.openstack.org/634112
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=1e76ddf711e392267c3da093e41c7935bf4493d6
Submitter: Zuul
Branch: stable/queens

commit 1e76ddf711e392267c3da093e41c7935bf4493d6
Author: Harald Jensås <email address hidden>
Date: Wed Jan 16 02:44:32 2019 +0100

    Fix port update deferred IP allocation with host_id + new MAC

    IP allocation was initially deffered due to lack of binding
    information. On port update with both `mac_address` and
    `binding_host_id`` in the request, 'fixed_ips: []' was
    appended to the new_port data. This caused the check for
    fixed_ips_requested to return True, which in turn cause
    deferred_ip_allocation to evaluates False.

    Only set the new_port default fixed_ips to original_ips if
    the original port had fixed_ips.

    Conflicts:
        test_segment.py

    Closes-Bug: #1811905
    Change-Id: If98a82f8432b09a29f9d0cc6627e9649b43bc4a1
    (cherry picked from commit b0d758e1b4af9aed8c2da6e0bac4723d8e4f5443)